This study targets IDUs, their networks and shooting galleries to evaluate the impact of an intervention that includes a stringent protocol for disinfecting injecting equipment and specially-designed procedures for promoting/reinforcing behavioral change. The emphasis upon these social groups and constructs is a significant departure from the conventional perspective on individual behavior. The design employs multi-disciplinary methods and incorporates three complementary levels of analyses that include 1000 individual members of approximately 150 drug using networks recruited from shooting galleries. Analyses of intervention-related changes will occur for each level, using data that are unique to specific levels as well as data that are common to other levels. The evaluation will employ a quasi-experimental design, using indicator data and macro-level ethnographic analyses to select three sets of neighborhoods, two to receive interventions and one to be a comparison. Participants enrolled from one of the designated intervention neighborhoods will receive a network-based intervention, and those from the second will receive a NIDA standard intervention. The comparison neighborhood group will be in another county and will receive minimal interventions (the usual counseling of IDUs, following CDC guidelines) after being interviewed to ascertain their risk relative to those in the network-based and standard intervention neighborhoods. Monitoring the comparison and intervention neighborhoods will assure equivalent characteristics between intervention and comparison group participants. Intensive ethnographic studies will be conducted to characterize networks using the selected shooting galleries. Ethnographically derived network-specific information will be used to revise an existing intervention design to draw upon network structure and dynamics in recruitment, the delivery of group-level elements of the intervention, and continuing contextual effects. The study design combines coordinated quantitative and qualitative analyses and continues the laboratory and intervention studies that were instrumental in the issuance of revised bleach cleansing recommendations by the CDC, CSAT and NlDA (CDC, April, 1993). The design of the network-based intervention will build upon the lessons learned from previous intervention and laboratory studies. The study will produce results that are generalizable to the many communities that cannot implement in the foreseeable future needle exchange or other accessible and acceptable programs providing personal sterile equipment. A tested intervention will be further refined and tested, using multi- level approach, and incorporating investigator-discovered knowledge about how participating IDUs engage in risky behaviors within shooting galleries and particularly within their networks. An RO1 proposal submitted by Dr. Paul Shapshak will assess the presence of HlV-1 and characterize HlV-1 molecular epidemiology in injection paraphernalia and among participating IDUs and their networks in these same shooting galleries. Dr. Shapshak's and the current proposal are submitted for review under the Investigator-lnitiated Interactive Research Project Grant (IRPG) program.